This invention relates to drill bits, specifically drill bit assemblies for use in oil, gas, geothermal, and horizontal drilling. More specifically, the invention relates to the shear bits having a high drilling efficiency while providing bit stability downhole during a drilling operation. The invention also relates to drill bits having elements that help to reduce wear while drilling, thereby extending the life of the bit.
U.S. Patent Publication US20030213621 to Britten et al. which is herein incorporated by reference for all that it contains, discloses a guide assembly for a core drill bit, which is at least partially guided at an inner wall of the core drill bit and projects radially with projections between the plurality of cutting inserts arranged on a frontal surface of the drill tube of the core drill bit, wherein a centering means projects at least axially, in part, beyond the cutting inserts, whereby the centering means is shorter than the axial length of the drill tube, and is axially spring-biased inside the guide assembly and has limited axial displacement.
U.S. Pat. No. 6,296,069 to Lamine et al., which is herein incorporated by reference for all that it contains, discloses a drill bit as used in particular in the oil well drilling field comprising a central body, cutting blades protruding with respect to the body, both at the front of this body according to a drill direction and at the sides of this same body, and cutting elements divided over an outer front surface and over an outer lateral well sizing surface comprised by each blade, wherein there are provided as cutting elements: in a central area of the front surface, on at least one blade: at least one synthetic polycrystalline diamond compact cutting disc, and in a remaining area of the front surface of this blade, situated beyond said central area with respect to the rotation axis, and on the other blades: thermally stable synthetic diamonds and/or impregnated diamond particles.
U.S. Pat. No. 5,244,039 to Newton, Jr. et al., which is herein incorporated by reference for all that it contains, discloses a rotary drill bit for drilling holes in subsurface formations comprising a bit body having a shank for connection to a drill string, a plurality of perform primary cutting elements mounted on the bit body and defining a primary cutting profile having a downwardly convex nose portion. There are associated with at least certain of the primary cutting elements respective secondary elements which are spaced inwardly of the primary profile. The distance of the secondary elements from the primary profile, when measured in direction perpendicular to said profile, is generally greater for secondary elements nearer the nose portion than it is for secondary elements further away from the nose portion, and is preferably such that the vertical distance of the secondary elements from the profile is substantially constant.